import com.mysql.jdbc.jdbc2.optional.MysqlDataSource;


import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class DBUtil {
    /**
     * 使用单例模式
     */
   private static DataSource dataSource=null;

    private static DataSource getDataSource() {
        if (dataSource==null){
            dataSource=new MysqlDataSource();
            ((MysqlDataSource)dataSource).setURL("jdbc:mysql://127.0.0.1:3306/MessageWall?characterEncoding=utf8&useSSL=false");
            ((MysqlDataSource)dataSource).setUser("root");
            ((MysqlDataSource)dataSource).setPassword("123456");
        }
        return dataSource;
    }

    public static Connection getConnection() throws SQLException {
        return getDataSource().getConnection();
    }

    public static void close(Connection connection, PreparedStatement preparedStatement, ResultSet resultSet){
        if (resultSet!=null){
            try {
                resultSet.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        if(preparedStatement!=null){
            try {
                preparedStatement.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        if(connection!=null){
            try {
                connection.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
}
